Federal Grid of Unified Energy System : Rosseti FGC UES to improve lightning-surge proofness of one of Moscow's main backbone transmission lines

Rosseti FGC UES to improve lightning-surge proofness of one of Moscow's main backbone transmission lines

06/11/2021

Rosseti FGC UES has commenced the second stage of work to install a new earth wire at the 500 kV Mikhailovskaya - Chagino transmission line with a branch to Kaluzhskaya substation. The work will protect the line from lightning strikes, improve the reliability of power supply to the South-Eastern administrative district of Moscow with over 1.4 mn people, a considerable part of consumers in the Moscow, Ryazan, and Kaluga regions, and a number of enterprises, too, including the Moscow Refinery. The cost of work is 87.7 mn rubles.

The obsolete earth wire will be replaced with a modern analog of Russian origin that is mechanically strong, thermally resistant, and stable to corrosion. Its service life is 25 years.

The installation is carried out 'under the tension' with the use of programmable machinery. In 2021, the 500 kV Mikhailovskaya - Chagino line will have 111 km of earth wire installed, including the portions across motorways and water obstacles. The total length of the earth wire mounted on this line will be 156 km, factoring in the scope of work done in the first stage of the project.

Statistically, about 27% of failures in the operation of main power lines in Central Russia are caused by lightning overvoltages. Earth wire is designed to protect power lines from direct lightning strikes and prevent short circuits that can cause damage to electrical equipment.

The length of the Mikhailovskaya - Chagino 500 kV power transmission line with a branch to the Kaluzhskaya substation is 347.6 km. The line joins the power systems of Moscow, Kaluga, and Ryazan.